Dramatic weather patterns the ‘new normal’

Experts say human-produced carbon dioxide is playing a big role in the warming of the atmosphere, which is having a major effect on the world’s oceans. Warmer oceans results in rising sea levels and more powerful hurricanes – but reversing the effects of global warming could take decades. NBC’s Robert Bazell reports.

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This content comes from Closed Captioning that was broadcast along with this program.

>>>the storm had the lowest low pressure ever recorded in the hemisphere. a storm like this has a way of making you ask questions like, what's happening to our world and our weather? and, yes, people are raising
global warming
already. our report tonight from our chief foreign correspondent
robert bazell
.

>> reporter: another
storm of the century
. a bit more than a year after the last one in the same place. most scientists have no doubt of the overall cause.

>>we have a new normal, really. it's the background environment for all
weather systems
has changed.

>> reporter: even some politicians agree.

>>anyone who says there's not a dramatic change in weather patterns, i think is denying reality.

>> reporter: everyone agrees that no single weather event can be attributed to the warming of the atmosphere, from human produced
carbon dioxide
. but many say it plays a big role.

>>human beings
don't make hurricanes but long term
climate change
can certainly interact with hurricanes and in some cases make them worse.

>> reporter: increasing
carbon dioxide
warms the air. the major effect is in the oceans.

>>the oceans are warmer than they used to be. not just at the surface, but below the surface.

>> reporter: hurricanes get their energy from warm oceans making them potentially more powerful. warmer oceans mean
rising sea levels
. the
sea levels
are higher now than they were a few decades ago. that means that every storm has a greater chance of washing over the levees just as sandy did.
global warming
by changing weather patterns also contributes to more intense droughts and wildfires as well. it will take decades to change. the new normal is likely to get worse before it gets better.
robert bazell
, nbc news, new york.